1. Field of the Invention
The invention relates to tanks used for transporting liquids, and more particularly to an improved internal baffle structure used to minimize wave motion in a free liquid surface and surging of liquid resulting from accelerations imparted to the tank during transportation.
2. Description of the Prior Art
In the transportation of large volumes of liquids in tank trucks it is well known that internal baffles are necessary to control surging and wave motion of the free surface in the liquid cargo, particularly transverse surging resulting from centrifugal forces experienced on curves and during turning. Without adequate baffling the entire vehicle may become unstable and even overturn, particularly where the tank is between 1/4 and 3/4 full and the free surface is large.
Many conventional tank truck designs use a single flat vertical longitudinal baffle bisecting the tank along the longitudinal axis. Frequently it has been observed that such a baffle is subject to severe wear resulting from incessant pounding of liquid waves against its surface. Such baffles frequently become dislodged and must be repaired or replaced after a few months of use.
The present invention solves these problems through the use of large longitudinal cylindrical baffles mounted between flat transverse support partitions, the entire assembly being rigidly attached to the interior walls of the tank vessel. This configuration greatly reduces and dissipates liquid surging and wave motion, while offering enhanced mechanical strength for the tank and baffle assembly.
Although the patent of Wright (U.S. Pat. No. 3,192,877) describes railroad tank cars containing numerous transverse cylindrical baffles, the present invention differs markedly from Wright with regard to construction, purposes and manner of operation. The Wright patent teaches that its invention controls longitudinal surging by dividing the liquid into "numerous increments of relatively small volume" (See Column 8, line 8), while the present invention effectively controls transverse surging and wave motion with a single large longitudinal cylindrical baffle in each section of the tank.
Various tanks using flat baffles or compartment partition walls, including some partially curved partition walls, are disclosed in the patents of Kramer (U.S. Pat. No. 1,462,347), Moxey (U.S. Pat. No. 2,049,132), Dalglish (U.S. Pat. No. 2,723,862) (also involving compartments for dry goods), and French Pat. No. 1,016,701. However, no patent or combination of patents known to the applicants shows or suggests the invention claimed herein.